Mortality after emergency surgery continues to rise after discharge in the elderly: Predictors of 1-year mortality

BACKGROUND: It is known that emergency surgery in the elderly is associated with high short-term mortality, but longer-term outcomes are not well described. We hypothesized that 30-day mortality may underestimate the true operative mortality experienced in this cohort. The purposes of this study were to characterize postoperative mortality rates extending to 1 year and to identify preoperative predictors of 1 year mortality after emergency abdominal surgery. METHODS We retrospectively reviewed the records of all patients older than 70 years who underwent emergency abdominal surgery at a major teaching hospital between 2006 and 2011. Demographics, preoperative physiology, prehospital status, body mass index, laboratory values, Charlson scores, comorbid conditions, American Society of Anesthesiologists classification, and operative details were recorded. The primary end point was 1-year mortality. Complementary log-log binary regression was used to determine independent predictors of death. Model discrimination was evaluated using the c statistic. RESULTS A total of 390 patients met our inclusion criteria. The mean age was 79 years, and 56% were women. Postoperative mortality was 16.2% at 30 days and 32.5% at 1 year, reflecting a doubling of mortality over 11 months. Independent preoperative predictors of 1-year mortality were Charlson score of 4 or higher (hazard ratio [HR], 1.79; 95% confidence interval [CI], 1.38-2.34), American Society of Anesthesiologists class of 4 or higher (HR, 1.66; 95% CI, 1.22-2.21), albumin less than 3.5 (HR, 1.71; 95% CI, 1.31-2.28), and body mass index lower than 18.5 (HR, 3.36; 95% CI, 1.48-6.86). The c statistic was 0.81. CONCLUSION The 1-year mortality after emergency surgery in the elderly is significantly higher than that at 30 days. We identified a constellation of preoperative clinical markers that were highly predictive of this poor late outcome. The presence of these findings in the emergency setting should prompt preoperative discussion about treatment goals and encourage surgeons to set realistic expectations about outcomes with the patient and family. Future studies will develop a clinical scoring tool that can be applied at the bedside to provide more effective counseling for this high-risk population.